Loads preferences from a topic. All settings loaded are prefixed
with the key prefix (default '').

>>

Loads preferences from text and optional metadata. All settings loaded
are prefixed with the key prefix (default ''). If $meta is defined,
then metadata will be taken from that object. Otherwise, $text will
be parsed to extract meta-data.

Package TWiki::Prefs::PrefsCache

The PrefsCache package holds a cache of topics that have been read in, using
the TopicPrefs class. These functions manage that cache.

We maintain 2 hashes of values:

{locals} Contains all locals at this level. Locals are values that only apply when the current topic is the topic where the local is defined. The variable names are decorated with the locality where they apply.

{values} contains all sets, locals, and all values inherited from the parent level

As each cache level is built, the values are copied down from the parent
cache level. This sounds monstrously inefficient, but in fact perl does
this a lot better than doing a multi-level lookup when a value is referenced.
This is especially important when many prefs lookups may be done in a
session, for example when searching.